Systems and methods for interacting with an implantable medical device

ABSTRACT

An interactive implantable medical device system includes an implantable medical device and a network-enabled external device capable of bi-directional communication and interaction with the implantable medical device. The external device is programmed to interact with other similarly-enabled devices. The system facilitates improved patient care by eliminating unnecessary geographic limitations on implantable medical device interrogation and programming, and by allowing patients, physicians, and other users to access medical records, history, and information and to receive status and care-related alerts and messages anywhere there is access to a communications network.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of U.S. patent application Ser. No.14/324,486, filed on Jul. 7, 2014, now U.S. Pat. No. 9,232,903, which isa continuation of U.S. patent application Ser. No. 13/783,143, filed onMar. 1, 2013, now U.S. Pat. No. 8,805,514, which is a continuation ofU.S. patent application Ser. No. 12/554,959, filed on Sep. 7, 2009, nowU.S. Pat. No. 8,543,208, which is a divisional of U.S. patentapplication Ser. No. 10/060,045, filed Jan. 29, 2002, now abandoned,each of which are assigned to the owner of the present application andare incorporated by reference herein in their entirety.

BACKGROUND

Field

The invention relates to implantable medical device systems, and moreparticularly to implantable medical device systems having the ability tocommunicate with devices outside of a patient for programming,interrogation, data retrieval, and other purposes.

Background

Epilepsy, a neurological disorder characterized by the occurrence ofseizures (specifically episodic impairment or loss of consciousness,abnormal motor phenomena, psychic or sensory disturbances, or theperturbation of the autonomic nervous system), is debilitating to agreat number of people. It is believed that as many as two to fourmillion Americans may suffer from various forms of epilepsy. Researchhas found that its prevalence may be even greater worldwide,particularly in less economically developed nations, suggesting that theworldwide figure for epilepsy sufferers may be in excess of one hundredmillion.

Because epilepsy is characterized by seizures, its sufferers arefrequently limited in the kinds of activities they may participate in.Epilepsy can prevent people from driving, working, or otherwiseparticipating in much of what society has to offer. Some epilepsysufferers have serious seizures so frequently that they are effectivelyincapacitated.

Furthermore, epilepsy is often progressive and can be associated withdegenerative disorders and conditions. Over time, epileptic seizuresoften become more frequent and more serious, and in particularly severecases, are likely to lead to deterioration of other brain functions(including cognitive function) as well as physical impairments.

The current state of the art in treating neurological disorders,particularly epilepsy, typically involves drug therapy and surgery. Thefirst approach is usually drug therapy.

A number of drugs are approved and available for treating epilepsy, suchas sodium valproate, phenobarbital/primidone, ethosuximide, gabapentin,phenytoin, and carbamazepine, as well as a number of others.Unfortunately, those drugs typically have serious side effects,especially toxicity, and it is extremely important in most cases tomaintain a precise therapeutic serum level to avoid breakthroughseizures (if the dosage is too low) or toxic effects (if the dosage istoo high). The need for patient discipline is high, especially when apatient's drug regimen causes unpleasant side effects the patient maywish to avoid.

Moreover, while many patients respond well to drug therapy alone, asignificant number (at least 20-30%) do not. For those patients, surgeryis presently the best-established and most viable alternative course oftreatment.

Currently practiced surgical approaches include radical surgicalresection such as hemispherectomy, corticectomy, lobectomy and partiallobectomy, and less-radical lesionectomy, transection, and stereotacticablation. Besides being less than fully successful, these surgicalapproaches generally have a high risk of complications, and can oftenresult in damage to eloquent (i.e., functionally important) brainregions and the consequent long-term impairment of various cognitive andother neurological functions. Furthermore, for a variety of reasons,such surgical treatments are contraindicated in a substantial number ofpatients. And unfortunately, even after radical brain surgery, manyepilepsy patients are still not seizure-free.

Electrical stimulation is an emerging therapy for treating epilepsy.However, currently approved and available electrical stimulation devicesapply continuous electrical stimulation to neural tissue surrounding ornear implanted electrodes, and do not perform any detection—they are notresponsive to relevant neurological conditions.

The NeuroCybernetic Prosthesis (NCP) from Cyberonics, for example,applies continuous electrical stimulation to the patient's vagus nerve.This approach has been found to reduce seizures by about 50% in about50% of patients. Unfortunately, a much greater reduction in theincidence of seizures is needed to provide clinical benefit. The Activadevice from Medtronic is a pectorally implanted continuous deep brainstimulator intended primarily to treat Parkinson's disease. Inoperation, it supplies a continuous electrical pulse stream to aselected deep brain structure where an electrode has been implanted.

Continuous stimulation of deep brain structures for the treatment ofepilepsy has not met with consistent success. To be effective interminating seizures, it is believed that one effective site wherestimulation should be performed is near the focus of the epileptogenicregion. The focus is often in the neocortex, where continuousstimulation may cause significant neurological deficit with clinicalsymptoms including loss of speech, sensory disorders, or involuntarymotion. Accordingly, research has been directed toward automaticresponsive epilepsy treatment based on a detection of imminent seizure.

A typical epilepsy patient experiences episodic attacks or seizures,which are generally electrographically defined as periods of abnormalneurological activity. As is traditional in the art, such periods shallbe referred to herein as “ictal.”

Most prior work on the detection and responsive treatment of seizuresvia electrical stimulation has focused on analysis ofelectroencephalogram (EEG) and electrocorticogram (ECoG) waveforms. Ingeneral, EEG signals represent aggregate neuronal activity potentialsdetectable via electrodes applied to a patient's scalp. ECoG signals,deep-brain counterparts to EEG signals, are detectable via electrodesimplanted on or under the dura mater, and usually within the patient'sbrain. Unless the context clearly and expressly indicates otherwise, theterm “EEG” shall be used generically herein to refer to both EEG andECoG signals.

As is well known, it has been suggested that it is possible to treat andterminate seizures by applying electrical stimulation to the brain. See,e.g., U.S. Pat. No. 6,016,449 to Fischell et al., and H. R. Wagner, etal., “Suppression of cortical epileptiform activity by generalized andlocalized ECoG desynchronization,” Electroencephalogr. Clin.Neurophysiol, 1975; 39(5): 499-506. And as stated above, it is believedto be beneficial to perform this stimulation only when a seizure (orother undesired neurological event) is occurring or about to occur, asinappropriate stimulation may result in the initiation of seizures.

It is especially beneficial to be able to tailor the operation of aneurostimulator (i.e., a device, preferably implantable, that deliversresponsive electrical stimulation therapy as described above) to thespecific needs of the patient. Accordingly, many neurostimulators andother implantable medical devices available and in development (inparticular cardiac devices, such as pacemakers and implantablecardioverter-defibrillators, or ICDs) are programmable to some extent.Typically, however, programming and interrogation are performed with anexpensive custom piece of equipment kept by the patient's hospital orclinic. To the extent a handheld or portable programmer is available toa patient, it is generally a standalone unit provided with a limitednumber of features and functions to avoid undesirable interference withthe implantable device's clinical objectives.

With traditional solutions, device interrogation and programming cangenerally only be accomplished locally, i.e., in close proximity to thedevice being interrogated or programmed. Programmers and handheldcontrol devices are relatively commonplace, but generally are not verysophisticated. Handheld devices are generally restricted to controllinga relatively small number of device parameters. Even other types ofprogrammers typically are not sophisticated enough to be tied intomultiple other devices or to have any ability to update or examine apatient's comprehensive treatment history, especially if the patient hasnot used that programmer before. Interaction with implantable medicaldevices has traditionally been limited by geographical considerations inthe past.

It will be appreciated that it is desirable to have improved flexibilityin managing patient care by enabling remote interrogation, programming,and interaction with implanted medical devices.

Modern implantable medical devices, such as neurostimulators,pacemakers, and ICDs, are capable of not only monitoring patientcondition and delivering therapy, but also can store detailed data anddiagnostics relating to a patient's condition for later retrieval.Analysis of this data can improve patient care dramatically, and allowfine-tuning the performance of the implantable devices by programmingthem with new operational parameters. Interrogation of an implantablemedical device allows data stored in the device to be retrieved by anexternal device (which, presumably, is better equipped to analyze thedata in great detail). After analysis, reprogramming the device allowsits performance to be optimized based on the interrogated data.

In addition to the clinical utility provided by flexible interrogationand programming capabilities as described above, it is also desirable tobe able to provide additional communications features to keep patientsinvolved, informed, and invested in their own care. Traditionalimplantable medical devices, even those using programmers or hand-heldcontrol devices, are not well suited for this. Long-term care ofepilepsy and cardiac patients, among others, requires a seriouscommitment from not only medical and clinical personnel, but also frompatients. As described above, anti-epileptic drugs often have unpleasantside effects, so patients taking them should be made to feel like theyhave the information and control they need to effectively manage theirdisease, or they may become complacent and non-compliant. The same istrue for patients with implantable medical devices—there is a dangerthat patients will take their devices for granted unless they aresufficiently involved.

Finally, it should be recognized that several tasks involved in thelong-term care and management of neurological and cardiac patients areeither labor-intensive or require inconvenient periodic office (orhospital) visits, even when the patient is being managed very well. Itwould be desirable to provide a mechanism for remote welfare-checks onpatients with implantable devices, to allow their progress to be checkedand data analyzed without the need for frequent office visits. Such acapability would preferably allow the user to store logs and notesregarding his or her condition, and would also facilitate the remoteadministration of examinations or surveys, as desired by the patient'streating medical team or physician.

Several others have attempted to leverage modern communicationscapabilities in the context of an implantable medical device system.

Medtronic, Inc. has tested an implantable diagnostic monitor for use intreating high-risk cardiac patients. See D. Sherman, “High-Tech HeartDevices Deliver Data Over the Web,” Reuters News Service (Aug. 8, 2001).However, the Medtronic devices used in the “Chronicle Study” appear tobe monitors only and do not appear to provide therapy. It would bepreferable to have a device that is not only a continuous monitor, butis also a closed-loop treatment system that can be programmed andoptimized with information obtained via the monitoring function.

Medtronic also has available a programmable implantable pulse generatorfor treating neurological disorders, particularly tremor. The “Activa”device has several programmable settings, but is not enabled fordiagnostic data storage and upload, and generally provides onlycontinuous (or semi-continuous) pulse streams, not closed-loop therapyresponsive to the detection of a relevant event. It is not adapted forremote control or administration.

Another company has developed a PDA-based system for monitoring patientstatus. See “MedSearch Technologies, Inc. Develops a RevolutionaryHome-Care Wireless Technology Using PDAs—Personal Organizers—as PatientMonitors,” Business Wire (Sep. 25, 2000). However, the MedSearch systemuses disposable sensors, and does not appear to tie into an implantabledevice system. Although a system such as the one from MedSearch mightprovide some additional convenience in the form of reduced officevisits, it is not directly involved in a closed-loop treatment systemand hence would not facilitate comprehensive remote patient care andmanagement, only monitoring.

St. Jude Medical, Inc. developed the Housecall trans-telephonic datalink system for implantable cardiac care devices. This device enabledthe transmission of stored data and diagnostics from the implantabledevice to a remote location. However, the apparatus was relativelycumbersome, and it took a relatively long time to complete a singlesession of data transmission, leading to patient non-compliance. Likethe systems described above, the Housecall system was intended toprovide a remote monitoring function only, and did not serve as part ofa closed-loop treatment system providing remote patient care.

Cyberonics, Inc. markets an implantable device for treating epilepsy; itis now also being tested for treating other disorders. The Cyberonics“NCP” (Neurocybemetic Prosthesis) is, in essence, an implantable pulsegenerator adapted, in this case, to apply electrical stimulation to thepatient's vagus nerve. Like the Medtronic Activa, it applies acontinuous or semi-continuous pulse stream, and only a few basicsettings are programmable. It is not adapted to collect data or toprovide responsive therapy, and no integrated system for networkcommunications is available.

Clearly, an interactive implantable medical device system with enhancednetwork communications capabilities, geographic independence, andclosed-loop treatment functionality would be desirable as it wouldgreatly improve patient care and management for numerous diseases anddisorders now treated with implantable devices that have only limitedcommunications capabilities.

SUMMARY

An interactive implantable medical device system according to theinvention avoids the shortcomings of the systems described above byenabling great flexibility and control over patient management and carein a closed-loop treatment system centering around the implantabledevice.

More specifically, an interactive implantable medical device systemaccording to the invention generally includes, in addition to theimplantable medical device, at least one external device capable ofbi-direction communication and interaction with the implantable medicaldevice. Preferably, the external device, which takes the form of ahandheld computing device, a base unit used in the patient's home, or aphysician-operated programmer, is also enabled to access acommunications network and interact with other similarly-enableddevices, such as other programmers and a database.

The capabilities of an interactive implantable medical device systemaccording to the invention facilitate improved patient care byeliminating unnecessary geographic limitations on device interrogationand programming—anywhere there is access to a communications network apatient's medical device can be queried and updated as necessary. Aphysician at a remote location can easily retrieve data not only fromthe implantable device but also from the patient's handheld computingdevice (which may include notes, annotations, seizure logs, and theresults of any surveys or examinations requested by the physician or thesystem), analyze it in whatever manner is most convenient and effective,derive new device settings from the data, and program the deviceremotely to accept the new parameters. The kind of detailed analysisallowed by a system such as the one described herein, which allows theconsideration of a far greater amount of diagnostic information thantraditionally available, further facilitates a greater understanding ofthe patient's condition and, ideally, any imminent risks. This isespecially true because the remote data collection and updatecapabilities allow data to be collected more frequently, allowing apatient's status and progress to be tracked in greater detail, even ifthe patient is not nearby. If a risk or some other urgent circumstanceis observed, the system permits messages and alerts to be provided tothe individuals who might need them—the patient, the patient'sphysician, and even field clinical support personnel if a devicemalfunction is suspected.

The system also permits a patient to have a much greater involvement andinvestment in his or her course of treatment, if such involvement isclinically desirable. Through the use of the handheld computing device,the patient can receive information, alerts, and messages about his orher condition, from the implanted device itself or from thecommunications network. If the patient has concerns about how the deviceis operating, a message can be sent to a physician or a note can bestored for later retrieval. This facilitates improved follow-up, evenwhen the patient's physician is not easily reached.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other objects, features, and advantages of the invention willbecome apparent from the detailed description below and the accompanyingdrawings, in which:

FIG. 1 is a diagram illustrating an exemplary basic exemplary personalcontrol unit (PCU) for use with an implantable device and acommunications network according to the invention;

FIG. 2 is a block diagram illustrating an exemplary implantable devicein communication with several illustrative network unit types accordingto the invention;

FIG. 3 is a block diagram of an embodiment of an implantable deviceaccording to the invention;

FIG. 4 is a block diagram of an embodiment of a generic network unitaccording to the invention;

FIG. 5 is a block diagram of an exemplary I/O subsystem of the networkunit illustrated in FIG. 4;

FIG. 6 is a block diagram of the functional structure of an exemplarydatabase according to the invention;

FIG. 7 is a flow chart illustrating an overall function and commandchart with command sources and validation steps required to processcommands;

FIG. 8 is a flow chart illustrating an exemplary data upload functionalprocess performed according to the invention;

FIG. 9 is a flow chart illustrating an exemplary software downloadfunctional process performed according to the invention;

FIG. 10 is a flow chart illustrating an exemplary parameter downloadfunctional process performed according to the invention;

FIG. 11 is a flow chart illustrating an exemplary seizure log entryfunctional process performed according to the invention;

FIG. 12 is a flow chart illustrating an exemplary quality of life surveyresponse functional process performed according to the invention;

FIG. 13 is a flow chart illustrating an exemplary generic command entryfunctional process performed according to the invention;

FIG. 14 is a flow chart illustrating an exemplary user alert functionalprocess performed according to the invention;

FIG. 15 is a flow chart illustrating an exemplary text note entryfunctional process performed according to the invention;

FIG. 16 is a flow chart illustrating an exemplary message sendingfunctional process performed according to the invention;

FIG. 17 is a flow chart illustrating an exemplary message receivingfunctional process performed according to the invention;

FIG. 18 is a flow chart illustrating an exemplary continuous monitoringfunctional process performed according to the invention;

FIG. 19 is a flow chart illustrating an exemplary system diagnosticsfunctional process performed according to the invention;

FIG. 20 is a flow chart illustrating an exemplary database queryfunctional process performed according to the invention;

FIG. 21 is a flow chart illustrating an exemplary storage management andhousekeeping functional process performed according to the invention;

FIG. 22 is a flow chart illustrating an exemplary user authenticationfunctional process performed according to the invention; and

FIG. 23 is a flow chart illustrating an exemplary compulsive userejection functional process performed according to the invention.

DETAILED DESCRIPTION

The invention is described below, with reference to detailedillustrative embodiments. It will be apparent that a system according tothe invention may be embodied in a wide variety of forms. Consequently,the specific structural and functional details disclosed herein arerepresentative and do not limit the scope of the invention.

Referring initially to FIG. 1, an implantable device 110 is illustrated.In the disclosed embodiment of the invention, the implantable device isa programmable neurostimulator for the treatment of epilepsy and otherneurological disorders. See U.S. application Ser. No. 09/896,092, filedon Jun. 28, 2001, for a description of an exemplary neurostimulator;U.S. Pat. No. 6,016,449 to Fischell et al. contains illustrative detailsof an alternative embodiment.

The present invention enables communication between the implantabledevice 110 and a communications network 112 (such as the Internet) byway of a personal control unit (PCU) 114 or a similar device (variousembodiments of which will be described in greater detail below). The PCU114 is adapted to receive user input 116 and to pass it along to thecommunications network 112 or the implantable device 110, asappropriate, and also to receive information from the communicationsnetwork 112 and the implantable device 110 and pass that information asuser output 118. It should be noted that the term “PCU” is used hereinfor any apparatus of the sort used to interact with an implantablemedical device system according to the invention, even if control is notspecifically possible and the device is used only for monitoringpurposes.

The PCU 114 communicates with the implantable device 110 via a wirelesslink 120 (typically inductive or RF), which in an embodiment of theinvention is accomplished through a special-purpose expansion module 122adapted to couple to an expansion connector of the PCU 114. In thisembodiment, the PCU 114 need not include a substantial amount of customhardware; it can be little more than a standard personal digitalassistant (PDA), such as a Palm Pilot®, PocketPC®, or other portable(and preferably handheld) computing device, programmed and interfaced toaccomplish the objectives described herein.

The PCU 114 typically also includes at least one data link 124 to thecommunications network 112. If the PCU 114 includes a built-in wirelesscommunication capability (operating under any of several knownprotocols, such as IEEE 802.11b, Bluetooth, or digital cellular), anantenna 126 might be built into the PCU 114 to facilitate the data link124. Alternative versions of the data link 124 are also possible,including part-time wired links (such as USB and Ethernet) from eitherthe PCU 114 or a docking station 128 to the communications network 112.Even if a wireless version of the data link 124 is available, it may bedesirable in some circumstances to also have a secondary link 130 fromthe docking station 128 to serve as a backup or alternative, operatingonly when the PCU 114 is docked in the docking station 128, in case thewireless data link 124 is either unavailable or undesired (e.g., in ahospital, airplane, or other electromagnetic interference-sensitiveenvironment). Some of all of the data links described above can beaccomplished either directly or through intermediate nodes andinterfaces, such as remote access servers.

The PCU 114 is operated in a manner similar to PDAs and other PDA-likedevices. Generally, a touch-sensitive screen is provided for user inputand output 116 and 118. A touch-sensitive input portion 134 is reservedfor writing with a stylus 136. In an alternative embodiment of the PCU114, a keyboard might be provided. Audio input and output, uses of whichwill be described in further detail below, are accomplished with amicrophone 138 and a speaker 140. For navigation and command purposes,several buttons 142 are provided on the PCU 114. These buttons can beused to command the PCU 114 to initiate special actions in a systemaccording to the invention, or can have the usual function assigned tosuch buttons in a standard PDA. A docking station button 144 is alsoavailable to indicate when it is desired to “synchronize” (i.e., sendand receive) data between the PCU 114 and the communications network112.

While the PCU 114 illustrated in FIG. 1 greatly resembles a traditionalPDA in form and operation, specialized peripherals and programmingenable operation of the PCU 114 according to the invention. It shouldalso be noted that alternative embodiments of the PCU 114 might takevery different physical forms. For example, instead of a handheldPDA-like design, a relatively stationary home base unit with a display,input provisions (such as a keyboard), and interfaces might also beused. A personal computer with the necessary interface peripherals(along the lines of the expansion module 122 and the antenna 126) andsoftware might also be used. These and other possible embodiments willbe described in further detail below.

FIG. 2 illustrates an exemplary network configuration according to theinvention. Accordingly, the network units illustrated in FIG. 2 areintended to depict a wide variety of different devices andconfigurations according to the invention, and likely do not reflect areal-world network topology or configuration.

The implantable device 110 is capable of communication with a widevariety of external devices. In addition to the PCU 114, the implantabledevice 110 is adapted for communication with a base unit 210 (which isin turn adapted for communication with the communications network 112either directly or through a remote access server 212), a mobile baseunit 214, a programmer 216, and a properly equipped personal computer218.

As described above, the PCU 114 is generally a handheld computer withenhanced communications capabilities and special-purpose programming foruse in a system according to the invention. The base unit 210 issimilar, but typically is a larger device not intended for mobile use.Accordingly, because of the different physical configuration, somechanges in equipment are possible and desirable. For example, a baseunit according to the invention would typically include a data entrykeyboard, a relatively larger display screen, and in most cases a wirednetwork connection (analog modem, ISDN, telephone line DSL, or DOCSIS oncoaxial cable), Ethernet, and other connectivity schemes are among thepossibilities).

In an embodiment of the invention, since the base unit is not mobile orportable, a hand-held “wand” coupled to the base unit 210 is included toestablish a short-distance communication link between the implantabledevice 110 and the base unit 210. A similar apparatus may be used withthe programmer 216 or the personal computer 218 to enable communicationswith the implantable device. Details of an exemplary wand will bedescribed in further detail below. It should be noted, however, that noseparate wand may be necessary if a longer-distance (e.g., at leastseveral meters) communications link is possible between the implantabledevice 110 and the base unit 210, or if the base unit 210 communicateswith the implantable device 110 exclusively through the PCU 114.

The base unit 210 is suitable for use by patients (and caregivers) whoeither cannot or prefer not to carry the PCU 114. It can also be used inconnection with the PCU 114, enabling a patient, caregiver, or otheruser to take advantage of the potentially larger form factor and otherfeatures (such as a full-sized keyboard and/or display screen) to moreeasily read and enter data and commands.

As referenced above, in one embodiment of the invention, the base unit210 serves as an intermediary between the PCU 114 and the communicationsnetwork 112. In this embodiment, the PCU 114 is provided with arelatively short-range network data link 124 (FIG. 1), such as one thatuses the IEEE 802.11b wireless networking protocol. The range of such anetwork data link 124 should be sufficient for convenient use.Alternatively, to give one example, the docking station 128 for the PCU114 can be connected via a wired link to the base unit 210, which wouldthen complete the network data link 124 to the communications network112 by periodically establishing a trans-telephonic connection to theremote access server 212.

The remote access server 212 is an apparatus that allows communicationsbetween any of the network units 114, 210, 214, 216, and 218 of theinvention and the communications network 112. It is not necessary in allcircumstances (for example, when one or more of the network units have adirect interface to the communications network), but frequently isemployed to translate between the protocols used for short-range andpoint-to-point networking (typically used on the “local” side 226 of thesystem illustrated in FIG. 2—i.e., relatively near the patient with theimplantable device 110) and the backbone technologies used by thecarriers and providers that provide access to the communications network112 (on the “remote” side 228 of the system—i.e., relatively far fromthe patient with the implantable device 110), for example via T1, T3,OC3, OC12, OC48, or OC192 lines. Accordingly, to accommodategeographically distributed users of a system according to the invention,multiple remote access servers would generally be used, and toaccommodate different local and remote communications protocols,multiple different types of remote access servers (such as modem pools,wireless network base units, LAN-to-WAN bridges and routers, and othernetwork interfaces and points of presence) can be employed. The singleremote access server 212 illustrated in FIG. 2 is intended to beillustrative in nature, and as shown, allows the base unit 210 and themobile base unit 214 to connect to the communications network 112. Othernetwork configurations are of course possible and consistent with theinvention described herein.

The programmer 216 is a device that is typically operated by medicalpersonnel (such as the patient's treating physician) to control theoperation of the implantable device 110. In general terms, theprogrammer 216 functions as a clinical interface to the implantabledevice 110, allowing its parameters to be modified, and for data and/orprogram code to be uploaded from and downloaded to the implantabledevice 110. For a more detailed explanation of an exemplary programmer,see U.S. patent application Ser. No. 09/977,052, filed on Oct. 12, 2001.Any given programmer may be located near the patient (as is the localprogrammer 216) or at a remote location (as are the remote programmers220). Unless it is desired to directly interrogate or program theimplantable device 110 using the local programmer 216, any of theprogrammers available in a system according to the invention can be usedto perform various programming functions. This will be explained infurther detail below.

A system according to the invention includes a database 222 and anetwork server 224. The database serves as a centralized data repositoryfor all data relevant to the operation of the system, and may includeclinical data, program code, and more. The centralized naturefacilitates the use of remote programmers 220 and any other remoteequipment enabled in a system according to the invention, as none of theprogrammers, base units, computers, or PCUs are necessarily 100% relianton locally stored data. One or more of these devices is preferablyconfigured to obtain data from and store data in the database 222.Accordingly, even if one of the remote programmers 220 has had noexperience with a particular patient or implantable device 110, thedatabase 222 is accessible to retrieve all of the information that wouldotherwise have been located only in the local programmer 216.

The network server 224 acts as the primary interface between thedatabase 222 and other devices attached to the communications network112. Although it might be possible and advantageous in certaincircumstances to communicate directly with the database 222, it isgenerally preferable to configure the network server 224 to receivequeries, perform necessary authentication, access the database 222, andrespond as necessary, thereby reducing the processing load on thedatabase 222 and also reducing the exposure of the database 222 tonetwork traffic (thereby improving security).

It should be noted that although a single database 222 and a singlenetwork server 224 are depicted in FIG. 2, this configuration is only anexemplary functional depiction of network structure. It is possible toachieve the goals of the present invention with multiple databasesand/or network servers, and it may be advantageous in certaincircumstances to use a distributed data repository rather than acentralized one, to facilitate load balancing and to increasereliability in the event of network and equipment outages.

It will be recognized that the network configuration illustrated in FIG.2 (like similar network configurations also within the scope of theinvention) enables continuity of treatment during travel by patient,clinician, or both. The multiple remote programmers 220 (or even asingle programmer attached to the communications network 112 remotely)allow a treating clinician or other authorized individual to monitor andtreat patients, adapt or change settings on the implantable device 110,or administer various aspects of the system from afar. And in additionto the remote programmers 220 illustrated in FIG. 2, it is possible tohave remote base units and PCUs, operated by the patient, a caregiver,or a clinician, capable of interaction with the system.

An overall block diagram of the implantable device 110 used formeasurement, detection, and treatment according to the invention isillustrated in FIG. 3. Inside the housing of the device 110 are severalsubsystems making up a control module 310. The control module 310 iscapable of being coupled to a plurality of electrodes 312, 314, 316, and318 for sensing and stimulation. Although four electrodes are shown inFIG. 3, it should be recognized that any number is possible, and in theembodiment described in detail below, eight electrodes are used. Infact, it is possible to employ an embodiment of the invention that usesa single lead with at least two electrodes, or two leads each with asingle electrode (or with a second electrode provided by a conductiveexterior portion of the housing in one embodiment), although bipolarsensing between two closely spaced electrodes on a lead is preferred tominimize common mode signals including noise.

The electrodes 312-318 are connected to an electrode interface 320.Preferably, the electrode interface is capable of selecting eachelectrode as required for sensing and stimulation; accordingly theelectrode interface is coupled to a detection subsystem 322 and astimulation subsystem 324. The electrode interface also may provide anyother features, capabilities, or aspects, including but not limited toamplification, isolation, and charge-balancing functions, that arerequired for a proper interface with neurological tissue and notprovided by any other subsystem of the implantable device 110.

The detection subsystem 322 includes an EEG analyzer function. The EEGanalyzer function is adapted to receive EEG signals from the electrodes312-318, through the electrode interface 320, and to process those EEGsignals to identify neurological activity indicative of a seizure, anonset of a seizure, or a precursor to a seizure. One way to implementsuch EEG analysis functionality is disclosed in detail in U.S. Pat. No.6,016,449 to Fischell et al., incorporated by reference above;additional inventive methods are described in detail below. Thedetection subsystem may optionally also contain further sensing anddetection capabilities, including but not limited to parameters derivedfrom other physiological conditions (such as electrophysiologicalparameters, temperature, blood pressure, etc.).

The stimulation subsystem 324 is capable of applying electricalstimulation to neurological tissue through the electrodes 312-318. Thiscan be accomplished in any of a number of different manners. Forexample, it may be advantageous in some circumstances to providestimulation in the form of a substantially continuous stream of pulses,or on a scheduled basis. Preferably, therapeutic stimulation is providedin response to abnormal events detected by the EEG analyzer function ofthe detection subsystem 322. As illustrated in FIG. 3, the stimulationsubsystem 324 and the EEG analyzer function of the detection subsystem322 are in communication; this facilitates the ability of stimulationsubsystem 324 to provide responsive stimulation as well as an ability ofthe detection subsystem 322 to blank the amplifiers while stimulation isbeing performed to minimize stimulation artifacts. It is contemplatedthat the parameters of the stimulation signal (e.g., frequency,duration, waveform) provided by the stimulation subsystem 324 would bespecified by other subsystems in the control module 310, as will bedescribed in further detail below.

Also in the control module 310 is a memory subsystem 326 and a centralprocessing unit (CPU) 328, which can take the form of a microcontroller.The memory subsystem is coupled to the detection subsystem 322 (e.g.,for receiving and storing data representative of sensed EEG signals andevoked responses), the stimulation subsystem 324 (e.g., for providingstimulation waveform parameters to the stimulation subsystem), and theCPU 328, which can control the operation of the memory subsystem 326. Inaddition to the memory subsystem 326, the CPU 328 is also connected tothe detection subsystem 322 and the stimulation subsystem 324 for directcontrol of those subsystems.

Also provided in the control module 310, and coupled to the memorysubsystem 326 and the CPU 328, is a communication subsystem 330. Thecommunication subsystem 330 enables communication between theimplantable device 110 (FIG. 1) and the outside world, particularly anexternal PCU 114 (FIG. 1), programmer 216 (FIG. 2), or other apparatusaccording to the invention. As set forth above, the disclosed embodimentof the communication subsystem 330 includes a telemetry coil (which maybe situated outside of the housing) enabling transmission and receptionof signals, to or from an external apparatus, via inductive coupling.Alternative embodiments of the communication subsystem 330 could use anantenna for an RF link or an audio transducer for an audio link.

Rounding out the subsystems in the control module 310 are a power supply332 and a clock supply 334. The power supply 332 supplies the voltagesand currents necessary for each of the other subsystems. The clocksupply 334 supplies substantially all of the other subsystems with anyclock and timing signals necessary for their operation.

It should be observed that while the memory subsystem 326 is illustratedin FIG. 3 as a separate functional subsystem, the other subsystems mayalso require various amounts of memory to perform the functionsdescribed above and others. Furthermore, while the control module 310 ispreferably a single physical unit contained within a single physicalenclosure, namely the housing, it may comprise a plurality of spatiallyseparate units each performing a subset of the capabilities describedabove. Also, it should be noted that the various functions andcapabilities of the subsystems described above may be performed byelectronic hardware, computer software (or firmware), or a combinationthereof. The division of work between the CPU 328 and the otherfunctional subsystems may also vary—the functional distinctionsillustrated in FIG. 3 may not reflect the integration of functions in areal-world system or method according to the invention.

Referring now to FIG. 4, a block diagram representing a generic networkunit 410 (of which the PCU 114, base unit 210, mobile base unit 214,programmer 216, and personal computer 218 of FIGS. 1-2 are all species)is set forth in detail.

The network unit 410 is a general-purpose or special-purpose computerprogrammed or adapted for use according to the invention. Accordingly,it includes a wide area communications interface 412 for communicationswith the communications network 112 (FIG. 1), and if it will be used toconnect to other nearby devices (such as the implantable device 110, thePCU 114, or the base unit 210), it also includes a local areacommunications interface 414. Preferably, both the wide areacommunications interface 412 and the local area communications interface414 are capable of bi-directional communications.

The network unit is controlled by a CPU 416. The CPU is coupled (eitherdirectly or through a bus controller, as is typical in the art ofcomputer design) to the wide area communications interface 412, thelocal area communications interface 414, a memory subsystem 418 (whichmight include ROM, DRAM, and other random-access memory) for programmingand short-term storage, a storage subsystem 420 (which might include ahard drive, flash memory, and other non-volatile storage), and aninput/output subsystem 422 used to pass information to and receiveinformation from a user. The input/output subsystem 422 will bedescribed in further detail below with reference to FIG. 5.

The operation of the network unit is controlled by a power supply 424and a clock supply 426. The power supply 424, in the case of a handheldunit such as the PCU 114, typically includes batteries, while othertypes of network units might receive power from AC outlets. Acombination of the two sources (as is common with laptop computers)might also be used. The clock supply 426 supplies substantially all ofthe other subsystems of the network unit with any clock and timingsignals necessary for their operation.

As with the implantable device 110, described above, it should beobserved that while the memory subsystem 418 is illustrated in FIG. 4 asa separate functional subsystem, the other subsystems may also requirevarious amounts of memory to perform the functions described herein andothers. Furthermore, while the network unit 410 (excluding the wand 428,if any) is preferably a single physical unit contained within a singlephysical enclosure, namely the housing, it may comprise a plurality ofspatially separate units each performing a subset of the capabilitiesdescribed herein. Some of the functions or subsystems of the networkunit 410 might be resident in a removable module, such as the expansionmodule 122 (FIG. 1). In particular, if a standard commercially availablecomputing device is used for the network unit 410 (such as a laptop ordesktop computer for the base unit 210 or the programmer 216), thencertain features (such as the local area communications interface 414,to give one example) might be added via insertion of a commercial orcustom peripheral, e.g., a PC Card. If a commercial handheld computer isused for the PCU 114, then other possibilities will be evident (e.g., aSpringboard® module for the Handspring Visor® line of PDAs).

It should be noted that the various functions and capabilities of thesubsystems of the network unit 410 described above may be performed byelectronic hardware, computer software (or firmware), or a combinationthereof. The illustration of FIG. 4 illustrates several of the majorfunctional subsystems present in a network unit consistent with theinvention. However, it should be noted that in many computing systems,other functional subsystems and modules are present that are notnecessarily reflected in FIG. 4. Moreover, an actual network unit 410according to the invention might integrate two or more of theabove-referenced subsystems. For example, the wide area communicationsinterface 412 and the local area communications interface 414 might beadapted into a single subsystem if efficiencies result therefrom.Accordingly, FIG. 4 is for purposes of illustration only, and does notnecessarily reflect the actual configuration of the PCU 114, the baseunit 210, the mobile base unit 214, the programmer 216, or the personalcomputer 218. It is, however, considered to be representative.

As described above, certain network units (such as the base unit 210,the programmer 216, or the personal computer 218) might include aconnected but separate wand 428 to enable a short-range, e.g.,inductive, wireless link to the implantable device. In such a networkunit 410, the local area communications interface 414 is generallyseparate from the remainder of the network unit 410 and is coupledthereto via a wire or other connection.

An exemplary embodiment of the Input/Output Subsystem 422 of FIG. 4 isillustrated in greater detail in FIG. 5. As shown, the Input/OutputSubsystem 422 includes an I/O Controller 510 capable of coordinating theactions of various portions of the subsystem. One or more of theportions 512-528 of the Input/Output Subsystem 422 illustrated in FIG. 5are optional; it should be noted that various embodiments of a networkunit 410 according to the invention will generally include only a subsetof the capabilities described herein. It would be unusual (thoughpossible) for a network unit to include all illustrated input and outputfacilities.

Some input possibilities are as follows. A keyboard 512, such as atraditional computer keyboard, can be used in connection with largernetwork units (such as base units and programmers). On smaller units, asmaller keyboard 512 can be made available (such as that provided on theBlackberry® handheld device by Research In Motion), or a “soft keyboard”can be provided in conjunction with a touch screen, such as on the Palmshandheld devices. It will be recognized that other data input paradigmsare also possible (that may be considered analogous to a keyboard, inthat alphanumeric and other data can be entered thereby) and known inthe art; such alternatives might take the place of the keyboard 512 in asystem according to the invention.

A microphone 514 (such as the microphone 138) can be used to receiveaudio input. This might be useful for several purposes, includingrecording audio messages for storage or transmission to remotelocations, for data input via speech recognition, or for biometricauthentication via voice recognition. Audio processing is relativelystorage and computationally intensive, so a network unit 410 havingspeech recognition or voice recognition capabilities according to theinvention would generally require a more powerful CPU 416 and morememory 418 and storage 420 than otherwise.

A pressure pad 516 (such as the input portion 134) can be used toreceive tactile and gestural input in a system according to theinvention. The pressure pad 516 can be used for data entry, for examplehandwriting recognition (either conventional handwriting or aspecial-purpose symbol set adapted for improved recognition accuracy,such as the Graffiti scheme used in Palm® handhelds). It can also beused as a pointing and selection device analogous to a “mouse” on adesktop computer system of the pressure pad found on many laptopcomputers. Other gestural sensors in addition to the pressure pad 516are also possible; for example, position and orientation detectors mightbe used advantageously in a system according to the invention for dataentry or pointing and selection.

A navigation control 518 (such as one or more of the buttons 142 or thejog wheel 143 of FIG. 1) is usable to effect pointing, selection, andnavigation through numerous menus provided by the software of thenetwork unit 410. In an embodiment of the PCU 114, for example, one ormore of the buttons 142 might be adapted to interpret pushes indifferent directions as different navigational controls. Similarly thejog wheel 143 might be used to navigate upward or downward within a menudisplayed on the PCU 114. In a desktop system, a mouse or trackballmight be used instead of buttons or a jog wheel. Various othernavigation controls are, of course, possible and consistent with theinvention described herein.

A biometric sensor 520 is available in an embodiment of the invention toauthenticate the user of the network unit 410. Exemplary biometricsensors include thumbprint, face, and retina scanners, keystroke timingrecognition devices, and chemical signature detectors. Numerous otherapproaches are possible. Although the biometric sensor 520 might beprovided in a network unit according to the invention, actual processingand authentication of biometric input need not be performed at thenetwork unit 410 receiving the input. Instead, data representative ofthe biometric input would be sent to a remote location, such as thedatabase 222, and processed there.

On a typical network unit 410, a display 522 is furnished to provideinformation to the user. On a handheld device, a liquid crystal display(LCD) is typically used, as the power and space requirements arerelatively small. On larger systems, such as the base unit 210, acathode ray tube (CRT) or other display mechanism might be feasible,although LCD technology is well suited for this application as well.

Aside from the display 522, a visual indicator 524 might also beprovided. It is common for commercially available handheld devices tohave one or more light-emitting diode (LED) visual indicators separatefrom the display, providing instant information regarding alerts andalarms, operational status, power supply, whether messages are waiting,and the like. It is contemplated that the visual indicator 524 in asystem according to the information would similarly provide readilyunderstood alert and status information.

A speaker 526 or other audio output device is furnished to provide forthe possibility of alarms, data output (via, e.g., tones, tonesequences, music, arbitrary sounds, or even recorded or simulatedspeech). The speaker 526 can also be used to accomplish a data link viaacoustic modulation (as in a traditional analog modem used fortrans-telephonic data communications). It is envisioned that in a systemaccording to the invention, the speaker 526 would generally be used toprovide alerts and alarms to the user, though other uses are certainlypossible and might prove advantageous in certain circumstances.

Finally, in the illustrative input/output subsystem illustrated in FIG.5, a tactile output 528 is provided. The tactile output 528 mightprovide one or more of several possible tactile experiences to theuser—a “nudge” sensation, a simulated texture, or (most probably)vibration to name but a few examples. The tactile output 528 can be usedto provide information to the user, and a vocabulary of tactilesensations might be established to facilitate relatively complexoutputs, but it is presently envisioned that a simple vibration alarm(as is often found on mobile telephones) is the most probable embodimentof the tactile output 528.

Consistent with the invention described herein (and with theillustration of FIG. 1), an embodiment of the PCU 114 would typicallyinclude a small LCD display, a pressure pad for navigation and dataentry, buttons and controls for navigation control, a visual indicatorfor power and/or message status, and a speaker or other small audiotransducer. Various embodiments of the PCU 114 might include a vibratingalert. The base unit 210, the programmer 216, or the personal computer218 might include a relatively larger CRT or LCD display, asubstantially full-sized keyboard, a microphone, a mouse or otherpointing device for a navigation control, and sound reproductioncapability. Likewise, the mobile base unit 214, though likely similar,might include a smaller display and keyboard. These configurations areintended for illustration only, and it should be noted that any aspectof the present invention might be alternatively configured if adifferent particular arrangement of capabilities is advantageous in anygiven context.

FIG. 6 is an exemplary block diagram of the database 222 and its networkserver 224 employed in an implantable device system according to theinvention. The database 222 and the network server 224 (which acts as aninterface to the database 222) jointly serve as a widely accessiblestorage repository 610 for various data types, including program code,patient information, and other data, as will be described in detailbelow.

As illustrated, the database 222 performs query processing, storagemanagement, application processing, and security management functions.These functions are performed by modules 612, including a queryprocessing module 614, a storage management module 616, an applicationprocessing module 618, and a security management module 620,respectively. Each of the foregoing modules 614-620 is generallyimplemented as software on a database server computing system(represented herein by the database 610), although it should be notedthat various modules may be combined in an implementation and that othermodules might also be present. Furthermore, the modules described hereincan be implemented in hardware, software, or a combination thereof.

The query processing module 614 is enabled to receive a query messagefrom the communications network 112 (and hence any network unit 410 in asystem according to the invention), process the query message andidentify responsive data in the database 222, and respond to theoriginating device. Accordingly, the query processing module 614performs a task that is fairly standard and common in database systems,though it should be noted that it is performed in a manner consistentwith the invention described herein.

The storage management module 616 is programmed to track the variousitems of data stored in the storage 610 of the database 222, manage theallocation of space, perform backups, and the like. The functionsperformed by the storage management module 616 are also generallyconsistent with those performed by known databases, though there may besome differences suggested in the practice of the invention.

The application processing module 618 is adapted to execute computerprograms (such as “servlets”) intended for use at the database 222. Forexample, any data processing required to accomplish authentication (ofusers and devices), encryption, compression, and data management isgenerally performed by the application processing module 618 illustratedin FIG. 6.

The security management module 620 handles any data involved in user anddevice authorization and authentication, password management, andaccount management. Although the functions performed by the securitymanagement module 620 are similar in some ways to the functionsperformed by the query processing module and other capabilities of thedatabase 222, the security functions are separated from other functionsto increase reliability and resistance to attack.

It will be appreciated, as is indicated above, that the database 222stores several types of information in its storage 610. In particular,the storage 610 includes two general categories of data: system data andoperating data. The first category, system data (essentially the staticcontent of the database 222, providing context for its operation),includes forms and graphics 622 used in collecting data from andreporting to the network units present in a system according to theinvention; any HyperText Markup Language (HTML) code 624 and the likeused to generate Web pages to be served to the system; a catalog ofmessages 626 in text, visual, audio, or other formats to be delivered tousers of devices in the system (which can be provided in multiplelanguages for users who need non-English access); an access log 628providing a detailed accounting of accesses (and attempted accesses) tothe database 222 for audit purposes; and the operative program code 630used by the database 222 (and particularly the application processingmodule 618). The second category, operating data (essentially thedynamic content of the database 222), includes patient information 632(vital data of the patients enrolled in the system who have theimplantable device 110), site information 634 (the facilities, such ashospitals, clinics, and assisted living homes, that are authorized andenabled to participate in the system), clinician information 636 (vitaldata of the physicians, nurses, and other personnel responsible forclinical patient management), and system information 638 (e.g., currentinformation on the state of the devices in the system, authorizationlists, password lists, storage and security policies, and otherlow-level information generally invisible and inaccessible to users).

Several exemplary relationships among the modules 612 and the varioustypes of data in the storage 610 are set forth below.

The query processing module 614 uses the forms and graphics 622 topresent a meaningful query context to a user, receives a query andstores it in the access log 628, and responds to the query usingadditional forms and graphics 622, the HTML 624, messages 626, programcode 630, and any patient, site, clinician, or patient information632-638 identified in processing the query. The query processing module614 provides the response to the originating device, which may be thePCU 114, the base unit 210, the mobile base unit 214, the programmer 216(or a remote programmer 220), the personal computer 218, or any otherauthorized network unit 410.

The storage management module 616 manages the dynamic content of thestorage 610, particularly the patient, site, clinician, and systeminformation 632-638.

The application processing module 618 is generally responsive to theprogram code 630. However, it should be recognized that the program code630 may be written to require access to various other data in thestorage 610, such as the patient, site, clinician, or system information632-638.

The security management module 620 is operative to access the access log628, the patient, site, and clinician information 632-636, and thesystem information 638 involved in data and system security (such asuser names and passwords). If data processing is necessary in performingauthorization or authentication checks, the program code 630 (and hencethe application processing module 618) might also become involved incertain circumstances.

Other function-data relationships should be evident, and may varyaccording to the specific application. Additional details of the role ofthe database 222 in connection with the operation of the presentinvention will be further described below.

As generally described above, the database 222 communicates with thecommunications network 112 (FIG. 2) through the network server 224.Generally, accesses to the database 222 will occur through a web server640 (one example of which is the Apache open-source web server) residenton the network server 224. The web server 640 includes an HTTP server642 in communication with the storage 610 of the database 222. The HTTPserver 642 processes and responds to any HTTP requests received by theweb server 640. If any server-level programs are required to be run, anapplication processing capability 644 resident on the web server 640 isavailable to handle such needs. For example, tasks related toauthentication 646 may be necessary before passing a request on to thesecurity management module 620 of the database 222; the applicationprocessing capability 644 is operative to perform such tasks.

Although it is generally understood that most accesses to the database222 will occur as HTTP requests arriving through the web server 640, itshould be recognized that other access techniques are possible. Forexample, instant-messaging protocols might also be used to pass data toand from the database 222. A messaging server 648 is also resident onthe network server 224; it is programmed to handleinstant-messaging-type transactions. Other protocols are also possible,and a server program adapted to handle other protocols 650 might also benecessary or advantageous.

FIG. 7 illustrates a number of possibilities representing procedures forinitiating an action in an interactive system according to theinvention.

A system according to the invention begins to perform an action uponreceipt of one or more of a large number of possible initiating events710. Although an action can be initiated at and performed by the samedevice in the system, that is not always or necessarily the case.Accordingly, it is instructive to consider the system in terms of aninitiating device, where the chain of events leading to performance ofan action begins, and an acting device, where the action is ultimatelycarried out. One or more additional network units may also participatein the process as supporting devices, acting as intermediaries, datasources, or simply as parts of the communications network 112.

In general, when an action is to be performed, a communication link isestablished (step 712) among the initiating device, the acting deviceand any supporting devices. To give one simple example, a physician at aremote location might command the interactive system to administer aquality of life survey to a patient. The process performed in doing so,and some details of quality of life surveys in general, will bedescribed in greater detail below. In this case, one of the remoteprogrammers 220, used by the physician, is the initiating device. Thepatient's PCU 114, used to administer the survey, is the acting device.There are several supporting devices: any intermediate communicationsnodes, such as the base unit 210 (between the communications network 112and the PCU 114) used to relay information between the remote programmer220 and the PCU 114; the database 222, where survey results areultimately stored; and the network server 224, which is generallyinterposed between the communications network 112 and the database 222.

It should be noted that the communication link established in step 712need not be real-time in all cases. To enable a system according to theinvention when one or more network units are either disabled ordisconnected from the network, certain data messages between networkunits can be deferred or queued by the transmitting device. Where amessage has high urgency or importance, the deferral or queuing may beaccompanied by a message to the user to establish a link (e.g., bydocking the PCU 114, moving into range of the base unit 210, orconnecting to a telephone line).

The user of the initiating device is then authenticated (step 714).Preferably, this is performed according to the method described belowand illustrated in FIG. 22. In general terms, user authenticationinvolves confirming with an authentication server, either locally orremotely, that the individual using the initiating device is who he orshe claims she is. This can be accomplished through login names andpasswords, biometrics, or any of a number of other known techniques.

The source, the initiating device itself, is then also optionallyauthenticated (step 716). This operation can be performed in a mannersimilar to the user authentication method set forth above. This is doneto ensure that the interactive system of the invention is not beingaccessed by an unauthorized device, which might lead to problems(especially if the access attempts are malicious). The type ofauthentication data used to authenticate the source would generally be anumeric code or other unique identifier either preset or programmed intoeach network unit used in accordance with the system.

Like other transactions in a system according to the invention, user orsource authentication can be deferred or queued if communication is notimmediately possible. In this case, a system according to the inventionwould preferably conditionally allow the desired transaction (or atleast any data entry related to the transaction), but not store it inthe database 222 or elsewhere until authentication is successfullycompleted. In other cases, for example when potentially confidentialpatient records are requested, transactions may be disallowed ifauthentication cannot be completed in real time.

The nature of the action to be performed is then analyzed and verifiedagainst one or more allowability rules (step 718). The timeliness of theaction (i.e., whether the action is being performed at an appropriatetime, given the user's history) is considered according to the methoddescribed below and illustrated in FIG. 23, and if the user isattempting to perform certain actions too often or at improper times,the action may be denied. Other desired criteria might also be applied.For example, certain users might be locked out from certain functions.

If user authentication, source authentication, and action verificationall complete successfully, then the desired action is performed (step720). As will be described in detail below, there are numerouspossibilities for the action to be performed. In particular, it ispossible to upload data from the implantable device 110 or any othernetwork unit (see FIG. 8), to download software to the implantabledevice 110 or another network unit (FIG. 9), to download detectionparameter sets to the implantable device 110 (FIG. 10), to handle theentry and storage of seizure logs (FIG. 11), to handle theadministration and storage of quality of life surveys,neurophysiological exams, and the like (FIG. 12), to allow a command tobe entered and processed (FIG. 13), to alert a device user to an urgentcondition (FIG. 14), to enter a note or annotation pertaining to data(FIG. 15), to send a message (FIG. 16), to receive a message (FIG. 17),to monitor EEG or other data in real time (FIG. 18), to perform systemdiagnostics (FIG. 19), or to query a database (FIG. 20). Other actionsare also possible and will be apparent to a practitioner of skill in theart.

As set forth above, a number of possible initiating events 710 can beused to cause one or more of the above-referenced actions to beperformed. For example, a neurological event detection 730 (typicallyobserved by the implantable device 110 of FIG. 1) can be used toinitiate the transmission of a message to a physician, alert one or moredevice users (such as the patient), or both. A detection by theimplantable device 110 or the PCU 114 that EEG storage is full or nearlyfull might also cause an alert and/or a message requesting that a dataupload be performed.

Similarly, a command 732 entered at the implantable device 110 (e.g., byaudio command, tapping, or magnet use), the PCU 114 (e.g., via any ofits input capabilities), the base unit 210, or the programmer 216, caninitiate nearly any of the possible actions performable by a systemaccording the invention. It is anticipated that each of the foregoingdevices might be able to accept different types of commands. Forexample, the implantable device 110 might receive commands by moving amagnet into and away from the vicinity of the device; the PCU 114 mightreceive commands via button presses, handwriting recognition, or voicerecognition; and the base unit 210, mobile base unit 214, programmer216, and personal computer 218 might all receive commands from akeyboard or pointing device.

For example, pressing a button on the PCU 114 (or entering a commandinto the handwriting input portion 134) might initiate a data upload, asoftware download, a seizure log entry, a note entry, a messagetransmission, real-time EEG monitoring, or a database query, to name buta few likely actions. Pressing a GUI button on the programmer 216 mightinitiate a data upload, a parameter download, real-time monitoring, ornumerous other options. There are too many possibilities to list themall; they would be apparent to a practitioner of ordinary skill in theart.

Various actions might be performed as a result of an entry in aprogrammed time schedule 734. For example, a scheduled event might causethe implantable device 110 to alert the patient to upload data. Otherpossibilities will be apparent with regard to the PCU 114, the base unit210, the programmer 216, or the database 222. In particular, routinescheduled entry of a quality of life survey might be scheduled at thePCU 114, the base unit 210, or the programmer 216. The database 222might perform maintenance or storage management tasks on a particularschedule. Any of the devices according to the invention might performdiagnostics at certain scheduled times. There are, of course, numerousother possibilities.

An action might be performed in response to a message 736 received bythe implantable device 110, the PCU 114, the base unit 210, theprogrammer 216, or the database 222. This feature, in an embodiment ofthe invention, can be considered a “remote command” capability—one ofthe network units is commanded to perform an action via thecommunications network 112 or some other communication link. Forexample, a command entry at the PCU 114 might cause the implantabledevice 110 to perform a certain action, such as store a record of EEGdata or switch modes—this would be accomplished via a messagetransmitted from the PCU 114 to the implantable device 110 (and alsopossibly to the database 222 for record keeping purposes). Many otherpossibilities will be apparent.

One or more actions can be performed as a result of a calculation 738performed by the implantable device 110, the PCU 114, the base unit 210,the programmer 216, or the database 222. For example, an evaluation ofrecently-uploaded EEG data at the programmer 216 or the database 222might indicate that a patient is particularly susceptible to seizuresover a time period in the near future; that calculation in an embodimentof the invention might cause an alert to the patient and/or a message tothe patient's physician to be generated automatically. Similarly, acalculation based on patient data uploads or other use of the systemmight be made at the PCU 114, the base unit 210, or the programmer 216to determine whether a message should be sent or a physician officevisit should be scheduled.

While it is observed above that a number of the communicationsoperations performed in a system according to the invention can bedeferred or queued if the communications network 112 is unavailable orshould not be used (e.g., wireless communications in a hospitalenvironment), the remaining portion of this specification will assumereal-time communications. Numerous possible alternate methods involvingdeferred or queued communications will be apparent to the reader.

FIG. 8 illustrates the process performed in uploading data stored by theimplantable device 110 to another device according to the systemaccessible via the communications network 112, such as the PCU 114, thebase unit 210, or the programmer 216.

Initially, the implantable device 110 identifies any new data to beuploaded (step 810). If there is any new data for upload (step 812), thenew data is transferred (step 814) over a link (such as the wirelesslink 120) to a target device, such as the PCU 114, the base unit 210, orthe programmer 216. Any suitable communications protocol can be used forthe link. The new data is then cleared (step 816) after it has beentransferred. Optionally, before the data is cleared, a handshaking orconfirmation operation between the implantable device 110 and the targetdevice can be used to confirm that the data transfer completedsuccessfully. Alternatively, the new data is not cleared upon everytransfer operation according to FIG. 8, but is cleared only upon commandfrom the target device (e.g., after the new data has been successfullystored and reconciled) or upon certain additional operations beingperformed such as programming (see FIG. 10). The recently transferrednew data is then sent on (step 818) to the database 222 for long-termstorage. At this stage, optionally, the new data can also be sent toother network units, such as the programmer 216 or a remote programmer220 to allow it to be analyzed or otherwise used.

If there is no new data for the device 110 to transfer (step 812), thenno transfer operation is performed. However, it should be noted that amessage to that effect (i.e., no new data) can optionally be sent to oneor more network units. See the description of FIG. 16, below.

The same process illustrated in FIG. 8 can also be used to uploadinformation from the PCU 114 or another device on the network 112 thatperiodically transfers information to the database 222 or elsewhere. Insuch an embodiment, the operation of clearing data (step 816) might beperformed differently under different circumstances—for example, the PCU214 and the programmer 216 are preferably programmed to retain someinformation even after a synchronization or transfer operation isperformed, such as a summary and log of the transferred data.Accordingly, the specific devices (e.g., the device 110, the PCU 114,and the database 222) are used as exemplary data sources and targets,and others are certainly possible within a system according to theinvention.

FIG. 9 illustrates the process used in a system according to theinvention to download new software and software updates from one deviceto another. For example, it is contemplated that software updates forthe implantable device 110 will reside in the database 222, buttypically will be transferred from the database 222 to another networkunit (such as the PCU 114 or the programmer 216, to name two) prior toprogramming the implantable device 110.

The process begins by examining the revision level of the software atthe source device, for example the PCU 114 or the programmer 216 (step910). The revision level of the software at the target device, forexample the implantable device 110, is then also checked (step 912). Ifthe target device has an older version of the software, then an updateis performed (step 914). The software program is transferred from thesource device to the target device (step 916) and installed. The sourcedevice's records are then updated to reflect the transfer andinstallation of the new software (step 918), and the target device'srecords are also updated accordingly (step 920). The originatingupdater, for example the database 222, is then notified that theimplantable device 110 (or other network unit) has received and isrunning the latest software update (step 922).

If the target device already has the newest software revision, then noupdate is performed (step 914) and the originating updater is informedthat no update was performed (step 922).

When the upgrade is complete, the target device verifies the integrityof the newly received code (for example, by comparing checksums orperforming other diagnostics). In an embodiment of the invention, if theupgrade failed, the old software remains operative, and if the upgradesucceeded, the new software replaces the old. The updating device isnotified accordingly (as in step 922), or alternatively, awaits a queryfrom the database 222 or other updating device.

Besides the implantable device 110, it might be desirable to enableother network units according to the invention to receive and acceptsoftware updates according to the method set forth in FIG. 9. Forexample, improved versions of the software operating on the PCU 114might be provided by the same mechanism. Additional functionality orreliability can also be provided this way for other network units,including the base unit 210 and the programmer 216.

When a new software version is deployed, it is frequently desired toupdate as many devices as possible within a short period of time.Accordingly, in an embodiment of the invention, the database 222 (orother network unit storing the software update) is enabled to perform anetwork broadcast or multicast of the software update to many networkunits (such as PCUs or programmers) simultaneously or substantiallysimultaneously, with the network units enabled to update the software intheir respective implantable devices (i.e., those implantable devicesthat are directly or indirectly connected) or other target devices. Thisprocedure is preferably performed as automatically as possible. Ifcertain target devices are unaccounted for after time has elapsed, andthose devices have not connected to any network unit for an upgrade ofthe sort described above, then messages can be sent to the patients orcaregivers responsible for the not-yet-upgraded target devices. Sendingmessages will be described in additional detail below with reference toFIG. 16.

As is described in greater detail in U.S. patent application Ser. No.09/977,052 (referenced above), optimum performance of the implantabledevice 110 is dependent on the use of patient-specific parameters andother device settings that are generally developed and calculatedoutside of the device 110. Such sets of parameters and settings aregenerally referred to, herein and elsewhere, as “templates.” Inparticular, it is contemplated that templates are developed by receivingraw patient-specific data from the implantable device 110 (or other datarecording apparatus), by the method illustrated in connection with FIG.8, above, processing the patient-specific data at the programmer 216 orthe database 222, developing a suitable patient-specific parameter set,and then updating the parameter set used by the implantable device 110by transferring it to the device 110.

An advantageous method for updating templates and parameters in theimplantable device is illustrated by the flow chart set forth in FIG.10. To start the process, the old parameter set is uploaded from thedevice 110 if necessary or desired (step 1010). This possibility isprovided to allow the programmer 216, if it was not the source of theold parameter set (and if it is not possible to access the database 222to otherwise obtain the old parameter set) to receive the old parameterset and use it as a starting point for modifications. Once modificationsare complete or a new parameter set has otherwise been obtained (step1012), the new parameter step is time-stamped for reference purposes(step 1014) and it is determined whether an update is necessary ordesired (step 1016). The decision to update is preferably left to thediscretion of the treating clinician.

If an update is desired, the new parameter set is downloaded (step 1018)to the device 110, and if successful, records in the source device(e.g., the programmer 216) and the target device (e.g., the device 110)are updated accordingly (steps 1020 and 1022, respectively). Theupdating device or other data repository, such as the database 222, isthen notified (step 1024) that a new parameter set is in place, oralternatively failure or success messages are sent upon query from thedata repository.

Also important to effective seizure and other neurological eventdetection according to the invention is the ability to annotate datareceived from the implantable device 110, that is, to correlate the rawdata with clinical observations. Such correlated clinical observationscan be a tremendous assistance in the development of patient-specificdetection parameter sets. Accordingly, as one of the goals ofimplantable medical devices is to facilitate patient independence,patients having such devices will not always be under direct medicalobservation. The patients themselves, however, can be a source ofinformation.

In traditional epilepsy care, for example, patients are often providedwith a seizure log, essentially a notebook in which to record dates,times, and symptoms of episodes they experience. Although entries madeby epilepsy patients are not definitively reliable, such entries can beuseful to clinicians in diagnosis, ongoing treatment, medicationmanagement, and other applications. And for purposes of parameter setdevelopment for the implantable device, seizure log entries serve a moredirect purpose. They enable the annotation of EEG data to indicate whereseizures occur and where automated detections should be occurring.Although EEG data will still typically be reviewed by a trainedepileptologist, seizure log information from the patient can improve theprocess dramatically by pointing out specific time periods of interestand reducing the (often tremendous) amount of raw data the clinicianmust examine. See U.S. patent application Ser. No. 09/977,052,referenced above, for additional details.

A system according to the invention is particularly well suited forfunctionality resembling that of a traditional paper seizure log. A PDA(such as the PCU 114) can be programmed to accept seizure-log-type datafrom the patient upon command. This kind of functionality isparticularly convenient in a portable device, such as the PCU 114,whether implemented in a PDA, mobile telephone, wristwatch, or otherform factor.

The flow chart of FIG. 11 sets forth a method for entering andprocessing a seizure log according to the invention. Initially, afterthe patient has indicated a desire to enter seizure log information tothe PCU 114 (for example, by entering a command 732), the seizure loginput is received by the PCU 114 or other apparatus (step 1110). Theinput is then processed (step 1112) to determine whether any action isnecessary (for example, if the entry indicates or suggests that anemergency is occurring or imminent). If an action is required (step1114), some respondent such as the patient's treating physician isalerted (step 1116, described in greater detail with reference to FIG.16), and if the desired action can be performed locally (step 1118) bythe device receiving the seizure log entry, then the action is performed(step 1120). The desired action can be pre-programmed into the PCU 114,received from a remote location such as the database 222, or directed bya physician or other individual at a remote location (e.g., operating aremote programmer 220 or other device connected to the communicationsnetwork 112). Examples of possible local actions include providing anaudio or visual alert to the patient, providing instructions to thepatient, or requesting the input of further information.

If the action cannot be performed locally (step 1118), a commandrepresentative of the action is relayed (step 1122) via thecommunications network 112 to another network unit capable of carryingout the command. For example, the implantable device 110 might becommanded to switch into a different detection mode, apply differenttypes of therapy, delivery an audio or somatosensory warning to thepatient, or go inactive. Other devices, such as the programmer 216 or aremote programmer 220 might provide an alert to a physician. Many otheroptions are possible and will be apparent to the reader hereof.

In any event, regardless of whether an action is required (step 1114),the input is stored (step 1124) for later retrieval. If there is moreinformation to be received (step 1126), the PCU 114 will receive andprocess whatever else is provided by the patient or operator (startingagain at step 1110). Otherwise, the records of the PCU 114 are updated(step 1128), and the input is acknowledged (step 1130) to the patient oruser.

While the PCU 114 is described above as the apparatus best suited forseizure log entry, it should be noted that the base unit 210, theprogrammer 216, or any other network unit according to the invention canbe provided with the same functionality, for use by the patient, acaregiver, or a clinical professional. In any event, upon upload (FIG.8), the seizure log and associated information will be transferred tothe database 222 and analyzed if necessary.

It is also desirable in some circumstances to be able to administersurveys and examinations to patients and their caregivers.Traditionally, this has required an office visit to allow the survey orexam to be administered under controlled conditions. However, it will berecognized that a system according to the invention affords onopportunity for automated and remote administration of surveys andexaminations.

One clinically useful tool is a quality of life (“QOL”) survey, which ingeneral is used to determine how well a patient is doing. Severalspecific QOL surveys are common in epilepsy treatment, including theQOLIE series (Quality Of Life In Epilepsy), which has a short version(QOLIE-10), a medium-length version (QOLIE-31), and a long version(QOLIE-89). For more information on QOLIE-10, see J. A. Cramer et al.,“A Brief Questionnaire to Screen for Quality of Life in Epilepsy: TheQOLIE-10,” Epilepsia 37(6): 577-582 (1996). For details on QOLIE-31, seeJ. A. Cramer et al., “Development and Cross-Cultural Translations of a31-Item Quality of Life in Epilepsy Inventory,” Epilepsia 39(1): 81-88(1998); and B. G. Vickrey et al., Quality of Life in Epilepsy QOLIE-31(version 1.0): Scoring Manual and Patient Inventory, Santa Monica,Calif.: RAND (1993). For more information on QOLIE-89, see O. Devinskyet al., “Development of the Quality of Life in Epilepsy Inventory,”Epilepsia 36(11): 1089-1104 (1995); and B. G. Vickrey et al., Quality ofLife in Epilepsy QOLIE-89 (version 1.0): Scoring Manual and PatientInventory, Santa Monica, Calif.: RAND (1993). Other surveys are alsoavailable, both epilepsy-specific (e.g., the ESI-55, see B. G. Vickreyet al., “A Health-Related Quality of Life Instrument for PatientsEvaluated for Epilepsy Surgery,” Med. Care 30: 299-319 (1992) and theWashington Psychosocial Seizure Inventory (WPSI)) and general (e.g., theSF-36 and SF-12 short forms), and ad hoc surveys and questionnairesmight be employed to advantage.

It is also advantageous to be able to administer variousneuropsychiatric examinations automatically, remotely, or through asystem according to the invention. Neuropsychiatric examinations mightbe useful for epilepsy patients and others being treated with animplantable medical device according to the invention. See, e.g., T.Onuma, “Classification of Psychiatric Symptoms in Patients withEpilepsy,” Epilepsia 41(Suppl. 9): 43-48 (2000); F. Lopez-Rodriguez etal., “Personality Disorders Among Medically Refractory EpilepticPatients,” J. Neuropsychiatry Clin. Neurosci. 11(4): 464-69 (Fall 1999);and V. M. Neppe et al., “Modern Perspectives on Epilepsy in Relation toPsychiatry: Behavioral Disturbances of Epilepsy,” Hosp. CommunityPsychiatry 39(4): 389-96 (April 1998). One example of a neuropsychiatricexamination that might be administered through a system according to theinvention is the Screening Cerebral Assessment of Neppe (the “BROCASSCAN”). See V. Neppe et al., “The Application of the Screening CerebralAssessment of Neppe (BROCAS SCAN) to a Neuropsychiatric Population,” J.Neuropsychiatry Clin. Neurosci. 4(1): 85-94 (Winter 1992). It should beunderstood that the BROCAS SCAN would advantageously be modified toreduce its reliance on direct clinician-to-patient interactions andsubjective analysis of responses; or alternatively, a real-time ordeferred link between the patient's PCU 114 and a clinician (at a remoteprogrammer, for example) can be established to permit such interactionsand analysis.

An advantageous method for administering a survey or examination isdetailed in FIG. 12. Initially, if a survey or exam is administered on acertain schedule 734 (FIG. 7), the patient or user is notified that itis time to respond to the desired survey or examination (step 1210). Aquality of life survey might be administered every three months, forexample, but other surveys and exams might be sought either more or lessfrequently. The schedule used may depend on clinical circumstances, forexample the nature of the patient's seizure log entries.

If the patient responds to the notification (step 1212), the survey orexamination is administered (step 1214) and the results are stored (step1216) for later retrieval. Optionally, the results can immediately betransmitted to another location, such as one of the remote programmers220 or the database 222. If the patient does not respond (step 1212), adeadline for response is checked (step 1218), and a patient reminder isscheduled (step 1220) if the deadline has not yet passed. If thedeadline has passed or is imminent (step 1218), a message is sent (step1222) to an appropriate individual or location (such as the treatingphysician or clinic) and records are updated (step 1224). In response,the treating physician can take whatever action is clinically indicated,such as rescheduling the survey or examination, or alternativelysummoning the patient in for an office visit (e.g., via the messagemechanism of the invention described with reference to FIG. 17). Uponupload (FIG. 8), the survey or examination results will be transferredto the database 222 and analyzed if necessary.

Many of the operations performed by an interactive system according tothe invention are initiated by way of a command 732 (FIG. 7) entered atone of the network units. As the term is used herein, a command canrefer to a specific directive to perform an action, or can be a director indirect consequence of any user-initiated action, such as enteringdata, pushing a button, speaking a phrase into the microphone 138 (FIG.1), docking the PCU 114 into the docking station 128, etc. A command canbe initiated or received at any of the network units described herein,including the implantable device 110 (e.g., by using a magnet or otherinteraction device), the PCU 114, the base unit 210 or the mobile baseunit 214, the programmer 216, the personal computer 218, or one of theremote programmers 220. There are numerous other possibilities, any ofwhich can constitute a command according to the invention.

A command can be processed according to the method illustrated in FIG.13. Initially, the command is received by a device (step 1310), whichfor the illustrative example provided here shall be the PCU 114. If thecommand can be executed locally (step 1312), the corresponding action isperformed (step 1314). As described herein, there are many possible anddesirable actions, including sending messages, storing information,changing modes, etc. If the command cannot be executed locally (step1312), it is relayed to the network unit capable of performing thedesired action (step 1316). The system's records are then updated (step1318) to reflect the command and any action performed, and the commandis acknowledged to the user (step 1320).

It may be necessary in the operation of a system according to theinvention to alert a user (such as a patient, caregiver, or physician)to a condition or event that requires urgent attention. The flow chartof FIG. 14 provides an exemplary method for receiving and handling suchalerts.

When an alert is received (step 1410) at any network unit, typicallyfrom the communications network 112, the implantable device 110, or someother communications channel, it is immediately processed (step 1412) todetermine what actions are required. If the alert can be deliveredlocally (step 1414) to the user, the alert is immediately delivered(step 1416). In general, an alert can be an audio, visual, orsomatosensory warning, a message, or some other form of communications.If the alert cannot be delivered locally (step 1414), it is relayed(step 1418) to the destination network unit.

If the alert requires a response (step 1420), the response is awaited(step 1422) for a desired period of time, either preset or programmed.If a response is received (step 1424), it is stored (step 1426) forlater retrieval or immediate transmission as a message (see FIG. 16).The system's records are then updated (step 1432) to reflect successfuldelivery of the alert, regardless of whether a response was required. Ifno response is received (step 1424), a message is sent (step 1428; seeFIG. 16) to a physician, caregiver or other individual capable offollowing up on the alert. The destination of the message may depend onthe nature of the alert. The system's records are then updated (step1430) to reflect the successful delivery of the alert and the user'sfailure to respond.

An alert provided according to the method illustrated in FIG. 14 can beprovided to the patient (preferably via the implantable device 110 orthe PCU 114) if the patient is in the best situation to respond to thealert, or to a caregiver (preferably via the PCU 114 or the base unit210) if the caregiver is best situated. It is also contemplated that incertain circumstances an alert can be provided to both the patient and acaregiver. Depending on the recipient's role, the information providedby the alert may differ. For example, a patient might be instructedsimply to seek immediate care, while a caregiver might be given moredetailed instructions on how to handle the urgent condition the alertpertains to. The different levels of information may be preset anddependent only on the recipient's general role, patient or caregiver, ormay be individually programmed depending on the circumstances and theclinical needs of different patients.

FIG. 15 illustrates an exemplary method used to associate notes andother data entries with data recorded by the implantable device. Thisfunctionality can be used by the patient to enter notes that correspondto stored EEG data (although the seizure log of FIG. 11 can be usedsimilarly), or simply to explain circumstances that might correspond toother measurements or data items stored by the implantable device 110,PCU 114, or other apparatus according to the invention. Initially, thepatient or other user enters a notation (step 1510), which is receivedby the device being used (typically the PCU 114). The notation is thenprocessed (step 1512), e.g., by compressing it if necessary andassigning it a date and time stamp. The notation is then associated andstored with any desired data (step 1514), for example stored EEGrecords, diagnostic information, seizure log entries, QOL surveyentries, etc.—the data to associate the notation with can preferably beselected by the user, or by default, can be given a date and time stampand simply stored with all data. The system's records are then updatedto reflect the notation (step 1516), and the entry of the notation isacknowledged to the user (step 1518). In an embodiment of the invention,any notations entered via the method specified in FIG. 15 are uploadedwith other data according to the flow chart of FIG. 8.

As referenced above, FIG. 16 depicts an illustrative method for sendingmessages from one apparatus to another in a system according to theinvention. A message (text, audio, image, or any other format) is inputby a user (step 1610) and received by the sending device. Typically, ina system according to the invention, the sending device will be the PCU114, the base unit 210 or mobile base unit 214, the programmer 216, orthe personal computer 218. The message is then processed (step 1612) toidentify its urgency and destination and to package the message fortransmission.

In an embodiment of the invention, the sending device is adapted toencrypt the message while processing it (step 1612), thereby enablingcommercial transactions involving financial data and the like. Forexample, if the patient is alerted that a certain medication change isnecessary, the user would be able to send an encrypted message (withcredit card or insurance coverage information) to a nearby pharmacy tohave the prescription filled and paid for. It should be noted thatencryption is useful in a broad array of contexts within a systemaccording to the invention, and in an embodiment of the invention,essentially all communications across the communications network 112 orvia wireless links will be encrypted to preserve the patient's privacyand security. It should be noted that certain communications protocols,such as the IEEE 802.11b protocol for wireless communications, includeencryption; a system according to the invention can either employ theprovided encryption or alternatively specifically encrypt the data(potentially enabling even greater security), depending on the needs ofthe system.

The message is transmitted to its destination (step 1614), eitherdirectly or indirectly, typically via the communications network 112,although shorter-range communications links may be used for localdevices.

If necessary, the message is associated with any data it might berelevant to (step 1616; see also FIG. 15), and system records areupdated accordingly to reflect the transmitted message (step 1618).Successful transmission of the message is then acknowledged to the user(step 1620).

If a reply to the message was requested (step 1622), a reply is awaitedfor a time period that can be either preset or programmed (step 1624).When a reply is received, it is associated in device storage with theoriginal message (step 1626) and displayed to the user (step 1628).

It should be noted that in an embodiment of the invention, traditionalInternet e-mail can also be used to send messages (FIG. 16) and alerts(FIG. 14) to patients and other individuals; such communications neednot be transmitted over the infrastructure established by the invention.

The technique used to process received messages is illustrated by theflow chart of FIG. 17. When a message is received (step 1710) from thecommunications network 112 or some other source, such as a local device,the recipient is immediately notified (step 1712). If a reply wasrequested (step 1714), entry of the reply is awaited (step 1716) for apreset or programmable time period. If a reply is entered (step 1718),it is transmitted back to the original message sender (step 1720), andsystem records are updated to reflect the message and the reply (step1722). If no reply was requested, the records are updated (step 1722) toreflect only the original message.

If a reply was requested (step 1714) and no reply was entered (step1718), it is determined whether a deadline has passed (step 1724). Ifthe deadline has passed, an automatic reply is sent (step 1726) and thesystem's records are updated accordingly (step 1728). The originalmessage sender may then decide how to follow up on the failure to reply.If the deadline has not passed (step 1724), a reply reminder is simplyscheduled (step 1730). It should be noted that the reply reminder, likeother scheduled events handled according to the invention, causes anaction to be performed at a certain time according to the specifiedschedule 734 (FIG. 7). Accordingly, at the proper time, the scheduledevent is treated essentially as a command according to the method ofFIG. 13, and can be performed locally or remotely, depending on thecircumstances.

Particularly in initial patient care for the treatment of epilepsy andother neurological disorders, it is useful to be able to monitor apatient's condition in substantially real time. This can be performed byan invasive surgical process to implant monitoring electrodes within thepatient's cranium, and can also be performed non-invasively with scalpelectrodes (which tend to have some disadvantages in comparison toimplanted electrodes). However, it will be recognized that if animplantable device 110 is already implanted in the patient and receivingdata from implanted electrodes, it is far preferable to be able tomonitor that data instead of using either of the alternate approaches.

Accordingly, FIG. 18 represents a method for performing real-timemonitoring of patient condition (including real-time EEG monitoring)according to the invention. As described above, the implantable deviceincludes a number of electrodes, an electronics package capable oftranslating the EEG signals received by the electrodes into digitaldata, and a communications capability. The method of FIG. 18 uses thosecapabilities for real-time monitoring.

Initially, a data link is established between the implantable device 110and the apparatus being used for monitoring (step 1810). Generally, themonitoring apparatus will be the programmer 216 or one of the remoteprogrammers 220. If a remote device is used, an indirect communicationslink may be necessary through a local device (such as the PCU 114 or thebase unit 210) and the communications network 112; other aspects of themethod operate in the same way.

Upon a specified, programmed, or commanded start time (step 1812), theimplantable device 110 collects some data (step 1814) and transmits itin a relatively small packet or short stream to the monitoring apparatus(step 1816). The monitoring apparatus then acts on the data, e.g., bydecompressing it, displaying it as a real-time EEG waveform, and storingit. If the real-time monitoring is finished (step 1820), then the datalink is closed (step 1822) and the end of monitoring is acknowledged(step 1824) to the patient and the user of the monitoring apparatus(e.g., by a message handled according to FIG. 16 or by some othermechanism). If the monitoring is to continue (step 1820), then the datacollection, transmission, and action steps (1814-1818) are repeated aslong as desired. It should be observed, of course, that real-timemonitoring can be performed only while a communications link is openbetween the implantable device 110 and other devices. Accordingly, whenshort-range wireless links are employed, it may be necessary to keep thewand 428 in close proximity to the implantable device 110 for asubstantial amount of time.

To ensure a system according to the invention is operating properly, itis necessary to be able to perform diagnostics. And in an interactivesystem according to the invention, it is advantageous to be able toensure abnormal diagnostic results are sent to and reviewed by theindividuals who most need to see them. A method for accomplishing thisis illustrated in FIG. 19.

To start the method, a diagnostic test is performed (step 1910) uponcommand, schedule, or automatically identified need. If the outcome ofthe test is abnormal (step 1912), and the user needs to be alerted (step1914), then an alert is provided to the user (step 1916) according tothe method described above with reference to FIG. 14. Even if the userdoes not need to be alerted (step 1914), there may be a need to alertothers (step 1918), such as a caregiver, physician, and in the case of amalfunction, the device's responsible technical and clinical personnel.If so, an alert is sent to an appropriate one of these individuals (step1920), and if still others need to be alerted (step 1922), additionalalerts are sent (step 1920) as necessary. These third-party alerts canbe sent as urgent messages according to the method of FIG. 16, forexample.

Once the user and any others have been alerted, the device failingdiagnostics attempts to respond (step 1924) and correct the situation.Various actions can be taken here that would depend on the clinical andtechnical circumstances; however, as a fail-safe, the implantable device110 (or other apparatus failing diagnostic testing) can be put into aninactive or passive monitoring state until further testing, possibly ata physician's office or other medical facility, can be performed. In anyevent, system records are updated (step 1926) to reflect the faileddiagnostic test, any alerts sent, and any actions performed to attemptto rectify the situation.

In an alternative embodiment of the invention, the device performingdiagnostics need not “know” that a diagnostic test has failed. In thisembodiment of the invention, diagnostics results are transmitted to aprocessing device (such as the programmer 216 or the database 222) via amessage (see FIG. 16) or data upload (FIG. 8); the processing devicethen evaluates the results and initiates any alerts or correctivemeasures necessary.

It should be noted that the method described above for performingdiagnostics applies equally to any of the devices used in a systemaccording to the invention, including the implantable device 110, thePCU 114, the base unit 210, the mobile base unit 214, the programmer 216(or one of the remote programmers 220), the personal computer 218, orthe database 222.

A patient or user having access to the PCU 114 or other network unitsaccording to the invention may have a need to access certaininformational records from time to time. For example, a patient whiletraveling might have an urgent need to identify a nearby physician whohas one of the remote programmers 220. The patient might also desire toreview a user's guide or other documentation relevant to the implantabledevice 110 or the system. The volume of information preferably madeavailable to a patient or other user might exceed the amount of storagepractically available on the PCU 114 or other accessible device, or maybe updated from time to time. Accordingly, there is a need forfunctionality enabling access to a wide variety of informationalmaterials, regardless of where they may be located in a system accordingto the invention.

It should further be observed that a physician or other clinicalprofessional using the programmer 216 or another apparatus may haveanalogous needs—e.g., to identify other nearby clinical professionalsand facilities, to access instructions or updated documentation, or toaccess a new patient's medical history. A query processing capability isprovided by a system according to the invention and will be describedwith reference to FIG. 20.

Initially, query input is accepted from the user (step 2010). This canbe accomplished via a navigable menu tree presented on a display,various drop-down lists of preset query choices, or free-form textentry, as desired. If the query can be handled locally (step 2012),e.g., if a physician query is entered into the PCU 114, and a list ofphysicians is maintained on the PCU 114, then the query is processed(step 2014) and interpreted, and the local data repository is accessed(step 2016) to find a response. A report representing the results (e.g.,one or more matching records from the repository) is then generated(step 2018). It will be recognized that it may be necessary to updatethe contents of the local data repository from time to time; this can beaccomplished by a method analogous to the software download describedwith reference to FIG. 9—the contents of the data repository can beconsidered a type of software module that needs to be updatedperiodically, and such an update can be scheduled or commanded asdesired.

If the query cannot be handled locally (step 2012), the query istransmitted (step 2020) to the database 222 or another location where itcan be handled. Results are generated at the remote location while thequeried apparatus awaits receipt of the results (step 2022).

Upon receipt from a remote location (step 2022), or upon localgeneration (step 2018), the results are presented to the user (step2024) by visual display, audio code or speech synthesis, or any othersuitable means (including the message transmission operation of FIG.16).

A basic device housekeeping method consistent with the invention isillustrated by the flow chart of FIG. 21. Because a substantial amountof data is stored, transferred, processed, and manipulated in a systemaccording to the invention, there may be, from time to time, old orsuperseded data that should be discarded or backed up to keep the systemoperating at maximum efficiency. The process described herein can beapplied to one or more network units (such as the implantable device110, the PCU 114, the base unit 210, the mobile base unit 214, theprogrammer 216 or remote programmers 220, the personal computer 218, orthe database 222), individually or in a coordinated effort.

The process begins by identifying any unnecessary data (step 2110) in adevice according to the invention. The unnecessary data, which istypically described as that data which is not necessary for any purposewhatsoever, is deleted (step 2112). Any old data, not referencedrecently or unlikely to be used, is then identified (step 2114) andbacked up (step 2116), typically on the database 222. The original copyof the old data is then deleted (step 2118). The backup copy of the olddata is still available if it is needed. Storage, including bothshort-term memory and long-term archival, is consolidated and organized(step 2120), preferably keeping like data together and maximizingcontiguous free space.

As illustrated in FIG. 7, the performance of certain actions accordingto the invention first requires authentication of a user (step 716) or adevice serving as the action's source (step 718). Such userauthentication is preferably performed in accordance with the methodsdescribed below and with reference to FIG. 22; device authentication isanalogous and will be described in further detail below.

The process begins by identifying a user (step 2210). In general, thisis accomplished by providing an identification data item to anauthentication server, which may be on the local device, the database222, or elsewhere connected to the communications network 112. Examplesof identification data items include user login names, numeric codesrepresentative of the user's identity, and biometric information; thereare numerous other possibilities.

If the user has already authenticated to the system (step 2212), and toomuch time has not yet elapsed (step 2214), the desired transaction isallowed (step 2216). The preset or programmable time limit exists toallow consecutive (and nearly consecutive) transactions to be performedwithout the need to perform detailed authentication for each one,relieving some burden on the system. This approach is well known.

If the user has not yet authenticated (step 2212) or if too much timehas elapsed (step 2214), then an authentication input is awaited fromthe user (step 2218). An authentication input according to the inventioncan be a password, a device-generated code, one or more items ofbiometric information, or any of various other known items. Oncereceived, the authentication input is tested (step 2220) by theauthentication server. If it is good (step 2222), and the useridentification and user authentication information match properly, thenthe transaction is allowed (step 2216). If not, and one or more retriesare allowed (step 2224), then authentication input is again awaited(step 2218) and the process continues. If no retries are available (step2224), then a failure message is sent (step 2226) to one or moreresponsible individuals (for example, the patient, the patient'sphysician, and a system administrator) or a failed access attempt issimply logged, and the transaction is denied (step 2228).

Finally, a method for ensuring patients and other users do not overusethe interactive functionality of a system according to the invention ispresented in FIG. 23. It has been observed that certain patients withprogrammable implantable medical devices tend to use interaction devicesmore often than recommended. This may lead to accelerated batterydepletion, inefficient system usage, and may make other unnecessarydemands on the system. The control method provided by the system andillustrated in FIG. 23 will reduce this tendency by limiting access toreasonable intervals.

To start, the system identifies the user making a request (step 2310)and further identifies the nature of the action being requested (step2312). For example, a given user may tend to try to upload stored datavery frequently, e.g., approximately every half hour while awake.Accordingly, after the user and the desired action have been identified,the system identifies a time restriction that corresponds to both theuser and the desired action (step 2314). Some users who use the systemappropriately might have no time restrictions, while others might havemultiple restrictions applying to multiple actions. The timerestrictions used by the system can be preset, programmed, commanded(e.g., by a physician), or dynamically and automatically generated andupdated by the system based on past behavior.

Once the appropriate time restriction has been identified, the user'shistory of interaction with the system, including the most recent actionof the same type requested by the user, is accessed (step 2316) and itstime is determined. The current time is checked (step 2316) and comparedto the time of the most recent action of the same type. If the timerestriction is met (step 2320), the action is permitted (step 2322) andrecorded by the system. Otherwise, permission to perform the action isdenied (step 2324).

It should be recognized, of course, that certain actions performed bythe system should never be restricted—for example, patients shouldalways be allowed to send urgent messages (see FIG. 16) or make aseizure log entry (see FIG. 11), and if an urgent message is to be sent,it should be possible for the patient to upload and transmit acorresponding EEG record for analysis (see FIG. 8). The system (and thePCU 114 or the implantable device 110) may not always be able toautomatically identify an urgent patient care situation or an emergency,so the patient must be given an opportunity to react to perceivedemergencies and seek appropriate care through the use of the system.

It should be observed that while the foregoing detailed description ofvarious embodiments of the present invention is set forth in somedetail, the invention is not limited to those details and a systemaccording to the invention incorporating an implantable medical devicecan differ from the disclosed embodiments in numerous ways. Inparticular, it will be appreciated that embodiments of the presentinvention may be employed in many different applications to monitor,communicate with, or control a medical device system. It will beappreciated that the functions disclosed herein as being performed byhardware and software, respectively, may be performed differently in analternative embodiment. It should be further noted that functionaldistinctions are made above for purposes of explanation and clarity;structural distinctions in a system or method according to the inventionmay not be drawn along the same boundaries. Hence, the appropriate scopehereof is deemed to be in accordance with the claims as set forth below.

The invention claimed is:
 1. An external apparatus comprising: acommunication subsystem configured to establish a wireless communicationlink with an implanted device; and a controller configured to: receive arequest to allow an action with the implanted device to occur, determineif the implanted device is authenticated, allow the action when theimplanted device is authenticated and an elapsed time requirement ismet, and deny the action until the implanted device becomesauthenticated.
 2. The external apparatus of claim 1, wherein thecontroller is configured to allow one or more authentication retrieswhen the implanted device is not authenticated or the elapsed timerequirement is not met.
 3. The external apparatus of claim 1, whereinthe controller is configured to authenticate the implanted device basedon an authentication code received from the implanted device.
 4. Theexternal apparatus of claim 1, wherein the controller is configured toauthenticate the implanted device based on biometric information.
 5. Theexternal apparatus of claim 1, wherein the action with the implanteddevice comprises at least one of uploading stored data from theimplanted device to the external apparatus, downloading new softwarecode from the external apparatus to the implanted device, downloading anew parameter set from the external apparatus to the implanted device,and receiving real-time EEG signals sensed by the implanted device. 6.An external apparatus comprising: a communication subsystem configuredto establish a communication link with an implanted device; and acontroller configured to: receive a request to allow an action with theimplanted device to occur, allow the action to occur when a timerestriction related to a past request to perform the action is met, anddeny the action when the time restriction related to a past request toperform the action is not met.
 7. The external apparatus of claim 6,wherein the time restriction is based on a frequency of past requests toperform the action and a nature of the action.
 8. The external apparatusof claim 6, wherein the time restriction comprises a restriction timeperiod, and the controller is configured to determine if the timerestriction is met by being further configured to: determine adifference between a current time corresponding to the time of therequest to perform the action, and a past time corresponding to the timeof a most recent past request to perform the action; wherein the timerestriction is determined to be met when the difference is at leastequal to the restriction time period, and not to be met when thedifference is less than the restriction time period.
 9. An externalapparatus comprising: a communication subsystem configured to establisha communication link with an implanted device implanted in a patient;and a controller configured to: determine whether the patient issusceptible to seizures based on an evaluation of EEG data of thepatient that was previously uploaded to the external apparatus, output acommand to the implanted device through the communication link, toinitiate real-time monitoring of EEG signals by the implanted devicewhen it is determined that the patient is susceptible to seizures,receive data from the implanted device through the communication link,the data corresponding to real-time EEG signals of the patient, andprocess the received data and display the received data as a real-timeEEG waveform.
 10. The external apparatus of claim 9, wherein thecontroller is further configured to: receive a request to output thecommand to the implanted device to initiate real-time monitoring of EEGsignals, and output the command only when a time restriction related toa past request to output the command is met.
 11. The external apparatusof claim 9, wherein the controller is further configured to: receive arequest to output the command to the implanted device to initiatereal-time monitoring of EEG signals, and output the command only whenthe implanted device is authenticated and an elapsed time requirement ismet.
 12. An implantable medical device comprising: a communicationsubsystem configured to establish a communication link with an externalapparatus; and a controller configured to: receive a command to initiatereal-time monitoring of EEG signals, establish a communication link withthe external apparatus, initiate real-time monitoring of EEG signalsonly when a time restriction related to a past request to output thecommand is met, and transmit data corresponding to real-time EEG signalsfrom the implantable medical device to the external apparatus throughthe communication link, when real-time monitoring is initiated.
 13. Animplantable medical device comprising: a communication subsystemconfigured to establish a communication link with an external apparatus;and a controller configured to: receive a command to initiate real-timemonitoring of EEG signals, establish a communication link with theexternal apparatus, initiate real-time monitoring of EEG signals onlywhen the external apparatus is authenticated and an elapsed timerequirement is met, and transmit data corresponding to real-time EEGsignals from the implantable medical device to the external apparatusthrough the communication link, when real-time monitoring is initiated.14. The implantable medical device of claim 12, further comprising adetection subsystem configured to detect a neurological event, whereinthe command to initiate real-time monitoring of EEG signals is receivedby the controller in response to a detection of a neurological event bythe detection subsystem.
 15. The implantable medical device of claim 13,further comprising a detection subsystem configured to detect aneurological event, wherein the command to initiate real-time monitoringof EEG signals is received by the controller in response to a detectionof a neurological event by the detection subsystem.